This invention relates to connecting devices for coupling liquid chromatography equipment, and in particular to a connecting device which permits simple and effective coupling of chromatography equipment with little or no effect on the efficiency of the equipment.
In the field of liquid chromatography, and in particular high pressure liquid chromatography, it is often necessary to couple two or more chromatography columns to one another, or to connect a column to another device, such as a valve. Connecting devices have been developed for effecting such coupling, and typically consist of a length of stainless steel tubing, individual ferrules for each end of the length of the tubing, and threaded fittings which are guided along the tubing and connect the opposite ends of the tubing between adjacent columns or other liquid chromatography equipment which is to be interconnected.
A serious deficiency of the prior art is the fact that the connecting device consists of at least five separate pieces (two end connectors, two ferrules and a length of tubing), which requires a considerable amount of time to complete the coupling. In addition, tools, such as a wrench for tightening the fittings, are required. Finally, because a fairly substantial length of tubing is required to accommodate the fittings and ferrules, the connector adds a certain volume to the equipment which is coupled, thus decreasing the overall efficiency of the coupled equipment.